1. FIELD OF THE INVENTION
The present invention relates to a multi-processor system which shares a main memory by a plurality of processors (CPU's).
2. DESCRIPTION OF THE PRIOR ART
As is well known, a computer system is equipped with an operating system (OS) to allow effective utilization of system resources and efficient operation of the computer system.
In a prior art multi-processor system in which a plurality of CPU's share one main memory, the OS offers controls necessary for the CPU's to carry out jobs. In this case, the following problems are encountered.
(1) A lock control to inhibit an access of the main memory by another CPU while one CPU accesses an area of the main memory to carry out a job is complex and maintenance of the OS is troublesome. PA0 (3) Because of lock competition, a performance improvement is not expected even if the number of CPU's is increased.
(2) The lock must be frequently secured and released. This leads to an increase of OS overhead.